User Manual

Download the BTS – continued
PRELIMINARY 2
SC 4812ET BTS Optimization/ATP – CDMA LMF
July 1999
3-26
Enable CSMs
Each BTS CSM system features two CSM boards per site. The GPS
receiver (mounted on CSM 1) is used as the primary timing reference
and synchronizes the entire cellular system. CSM 2 provides redundancy
(but does not have a GPS receiver).
The BTS may be equipped with a LORAN–C Low Frequency Receiver
(LFR), or external 10 MHz Rubidium source which the CSM can use as
a secondary timing reference. In all cases, the CSM monitors and
determines what reference to use at a given time.
– Each CSM (of a redundant pair at each BTS) is
associated with “partner” MCCs. CSMs must be
enabled before the partner MCC can be enabled.
– The CSM(s) and MCC(s) to be enabled must have
been downloaded with code (Yellow, OOS–RAM)
and have been downloaded with data.
– Verify the CSM configured with the GPS receiver
“daughter board” is installed in the frame’s CSM 1
slot before continuing.
IMPORTANT
*
Follow the steps outlined in Table 3-18 to enable the CSMs installed in
the C–CCP shelves.
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